Workflow systems, as generally known, comprise an ensemble of programs, and the programs communicate with each other by passing parameters. A parameter can represent any kind of data such as integers, strings and floating point values.
As also is generally known, a symbol table is a data structure that facilitates the process of inserting, searching, and modifying parameters. Symbol tables are extensively used in parallel systems, compilers, and other settings. Typically, a lookup scheme in the context of a symbol table is pre-set or fixed, and/or gives priority to local definitions. However, this presents a lack of flexibility that severely limits the applicability of such schemes (and symbol tables) to a broader range of contexts.